BIRDS OF NORTH AND MIDDLE AMERICA 647 



to, or longer tlian, the outermost one, and averaging more whitish 

 below, the dark sepia streaks somewhat smaller; both uniform and 

 spotted-backed individuals occur as in ohsoletus. The dark variety 

 of the young gray phase of the latter does not occur in the present 

 subspecies. 



N'atal down. — Unknown. 



Adult male.— Wing 349.2-361.9 (355.8); taH 203.2-238.7 (214.7); 

 culmen from cere 22.8-23.3 (22.9); tarsus 58.4-63.5 (61.5); middle 

 toe without claw 48.2-50.8 (50.0 mm.)." 



Adult female.— Wing 383.5-419.1 (400.4); tail 233.8-266.7 (249.8); 

 culmen from cere 24.1-27.9 (25.6); tarsus 57.1-67.3 (54.8); middle toe 

 without claw 50-54.6 (52.8 mm.).^^ 



Range. — Breeds in Arctic Eurasia from the Archangel district of 

 northern Russia eastward across northern Siberia (Sagastyi-, Lena 

 Delta; Chuckche Peninsula; Ikauria; Chubukulach River) to Kam- 

 chatka, Bering Island, and Amiu-land, and to the Bering Sea coast of 

 Alaska (Nulato, St. Michael, St. Lawrence Island, Nushagak, Norton 

 Bay), intergrading in Alaska wth ohsoletus (two birds from Fort 

 Anderson, Northwest Territories, Canada, are more like uralensis 

 than like ohsoletus!). 



Winters southward to the Ural Mountains and Amurland, Sakhalin, 

 the Kurile Islands, Japan (Hokkaido), and probably to the Aleutian 

 Islands as well, south to Washington. Occasional on St. Pauls Island 

 and St. Georges Island, and Washington (Spokane). 



x4.ccidental in North Dakota (11 miles northeast of Wilton, Decem- 

 ber 15, 1940; specimen in U. S. Nat. Mus.) 



Type locality. — Ural Mountains. 



Falco gyrfalco Pallas, Zoogr. Rosso-Asiat., i, 1826, 324. — Bunge, Mel. Biol. 



Acad. Imp. Sci. St. P6tersbourg, xi, livr. 4, 1882, .592 (Sagastyr, Lena Delta, 



Siberia) . 

 Falco sacer Dall and Bannister, Trans. Chicago Acad. Sci., i, pt. 2, 1869, 271 



(Nulato, Alaska). — Coxjes, in Elliott's Rep. on Affairs in Alaska, 1875, 179 



(St. Paul Island). 

 Hierofalco gyrfalco sacer Bean, Proc. U. S. Nat. Mus., v, 1882, 161 (Bering Sea, 



near St. Georges Island). 

 Falco gyrfalco var. candicans Schrenck, Reise Amurl., i, 1860, 228 (Amurland). 

 Falco candicans Dall and Bannister, Trans. Chicago Acad. Sci., i, 1869, 271, 



part (Alaska). — Saunders, Ibis, 1883, 350 (Bering Sea). 

 Falco (Hierofalco) gyrfalco var. candicans Ridgway, in Baird, Brewer, and Ridg- 



way's Hist. North Amer. Birds, iii, 1874, 108, 111 part (Bering Straits; 



Ural Mountains). 

 Hierofalco gyrfalco candicans Nelson, Cruise Corwin in 1881, 1883, 77 (Bering 



Straits) . 



'^ Eight specimens from Alaska, Bering Island, and Kamchatka. 

 38 Fifteen specimens from Alaska and Bering Island. 



